A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 2 2 1 2 NANOTECHNOLOGY NANOLATTICES THAT DISSIPATE ENERGY A new material property of 3D nanostructures was discovered for the first time by scientists from the University of Texas at Austin and North Carolina State University, Raleigh. Until now, the unique property—anelasticity, or how materials react to stress over time—had only been found in simple nanostructures like nanowires. In addition to the discovery, the research team also uncovered the internal mechanics of the materials that make this property possible. Researchers studied the anelastic phenomenon by observing how oxide-based nanolattices reacted to bending. The tiny defects moved slowly in response to the stress gradient. When the stress was released, the tiny defects slowly returned to their initial positions, resulting in the anelastic behavior. The researchers also found that when these defects move back and forth, they unlock energy dissipation characteristics. The material could potentially serve as a shock absorber, but because it’s so thin and lightweight, it would be on a very small scale. The researchers say it could have applications in chips for electronics or other integrated electronic devices. Now that they have discovered these anelastic characteristics, further work will focus on how to manipulate them for specific uses. The researchers will examine the geometry of the nanostructures and experiment with different loading conditions to determine how they can optimize the anelastic performance for energy dissipation applications. utexas.edu, ncsu.edu. NANOMATERIAL MADE FROM FISH WASTE Using a simple and convenient method, a research team at Nagoya Institute of Technology in Japan created carbon nano-onions (CNOs) from fish waste. To do this, the team developed a synthesis route in which fish scales extracted from fish waste after cleaning are converted into CNOs in mere seconds through microwave pyrolysis. The novel approach is groundbreaking as it requires no complex catalysts, harsh conditions, or prolonged production. Moreover, this synthesis process yields CNOs with very high crystallinity—a property that’s difficult to achieve in processes that use biomass waste as a starting material. Additionally, during synthesis, the surface of the CNOs is selectively and thoroughly functionalized with carboxylic acid and hydroxyl groups. This is in stark contrast to the surface of CNOs prepared with conventional methods, which is typically bare Nanolattices are tiny, hollowmaterials similar in structure to sea sponges. and must be functionalized through additional steps. Yet another advantage associated with automatic functionalization and high crystallinity is that of exceptional optical properties. To showcase some of the many practical applications of the CNOs, the team demonstrated their use in LEDs and blue light-emitting thin films. The CNOs produced a highly stable emission, both inside solid devices and when dispersed in various solvents, including water, ethanol, and isopropanol. Furthermore, the proposed synthesis technique is environmentally friendly and provides a straightforward way to convert fish waste into infinitely more useful materials. The work may help fulfill several of the UN’s sustainable development goals. Additionally, if CNOs make their way into next-generation LED lighting and QLED displays, they could significantly reduce manufacturing costs. www.nitech.ac.jp/eng. Triangular holes make this material more likely to crack from le to right. Courtesy of N.R. Brodnik et al./Phys. Rev. Lett. Researchers at the University of California, Riverside demonstrated a new magnetized state in a monolayer of tungsten ditelluride. Called a ferromagnetic quantum spin Hall insulator, this one-atom-thick material has an insulating interior but a conducting edge, which has important implications for controlling electron flow in nanodevices. ucr.edu. BRIEF A synthesis procedure developed by NITech scientists can convert fish scales obtained from fish waste into a useful carbon-based nanomaterial. Courtesy of Takashi Shirai.
RkJQdWJsaXNoZXIy MTYyMzk3NQ==